This invention resulted from a contract with the United States Department of Energy and relates to an inspection device. More particularly, the invention relates to an ultrasonic probe placed in a double-wall tube to detect flaws at the interface between concentric walls thereof.
U.S. Pat. No. 4,037,465, issued on July 16, 1977, to K. Cook, D. Koerner, R. Conningham, Jr., and G. Murrin, Jr. (three of whom are co-inventors of the invention presented herein), discloses an ultrasonic probe which can be used to conveniently and effectively inspect a single-wall tube from the bore side thereof. However, for inspecting duplex (i.e., double-wall) tubes used in apparatus such as heat exchangers, the proper use of the inspection probe of the aforesaid patent require supplemental information to adjust both flaw detection and sensitivity. The supplemental information must elevate the interface for some reflection-transmission characteristics.